Lewis & Short

Pompējus (trisyl.) or Pompēïus (quadrisyl.), i, m., and Pompēja, ae, f., name of a Roman gens. So the famous Cn. Pompejus Magnus, the triumvir, Caes. B. C. 3, 86; Cic. Fam. 3, 4, 2; 13, 41, 1; id. Imp. Pomp. 1 sqq. et saep.
In fem., Pompeja, his sister, Cic. Fam. 5, 11, 2; another, his daughter, Hirt. B. Afr. 95, 3; a third, daughter of Q. Pompeius, wife of Julius Cœsar, divorced from him, Suet. Caes. 6; 74.
Hence,

  1. A. Pompējus (Pompēïus), a, um, adj., of or belonging to a Pompey, Pompeian: domus, Ov. P. 4, 5, 9: lex, Caes. B. C. 3, 1: porticus, at Rome, Prop. 2, 23, 45 (3, 30, 11); cf. Plin. 35, 9, 35, § 59; Suet. Caes. 81: via, leading through Sicily, Cic. Verr. 2, 5, 66, § 169: ficus, Plin. 15, 18, 19, § 70.
  2. B. Pompējānus, a, um, adj., of Pompey, Pompeian: equitatus, Caes. B. C. 3, 58: classis, id. ib. 3, 101: triumphi, Luc. 3, 166: caedes, id. 10, 350: porticus (usually called Pompeja porticus), Vitr. 5, 9: theatrum, Mart. 6, 9; 14, 29; hence also, Notus, which blew in Pompey’s theatre, id. 11, 21: ficus (also called Pompeja ficus), Cloat. ap. Macr. S. 2, 16: partes, Sen. Ep. 71, 9.
    1. 2. Subst.: Pompējāni, ōrum, m., the adherents or soldiers of Pompey, Pompey’s party, Pompey’s troops, Caes. B. C. 3, 46; Vell. 2, 52, 4; Sen. Ira, 3, 30, 5.
      In sing., Tac. A. 4, 34: Pompejanus Cilix, Luc. 4, 448.